ACS BIOCHEMISTRY ACTUAL TEST
QUESTIONS WITH COMPLETE SOLUTION
PREMIUM REVIEW CONTENT
●● What is the Henderson-Hasselbalch equation used for?
Answer: It is used to calculate the pH of buffer solutions based on the
concentrations of the acid and its conjugate base.
●● What is the physiological pH maintained by the bicarbonate system
in blood?
Answer: Around 7.4.
●● How are amino acids classified?
Answer: Based on their side chain properties: nonpolar, aromatic, polar
uncharged, acidic, and basic.
●● What are zwitterions?
Answer: Molecules that possess both positive and negative charges at
physiological pH.
●● What is the isoelectric point (pI)?
Answer: The pH at which an amino acid has no net charge, calculated as
pI ≈ (pK₁ + pK₂)/2.
,●● What are fibrous proteins?
Answer: Proteins that provide structural support, with elongated
structures and repetitive secondary motifs, such as collagen and keratin.
●● What are globular proteins?
Answer: Compact and soluble proteins that perform diverse functions,
such as enzymes and hemoglobin.
●● What is the primary structure of a protein?
Answer: The linear sequence of amino acids that determines the
protein's unique characteristics.
●● What defines the secondary structure of a protein?
Answer: Regular patterns such as α-helices and β-sheets formed by
hydrogen bonding between backbone atoms.
●● What is the tertiary structure of a protein?
Answer: The three-dimensional shape formed by the folding of the
polypeptide chain, stabilized by various interactions.
●● What is the quaternary structure of a protein?
Answer: The assembly of multiple polypeptide subunits into a functional
protein complex.
, ●● What is chromatography used for in protein purification?
Answer: It separates proteins based on size, charge, or binding affinity.
●● What does SDS-PAGE stand for?
Answer: Sodium dodecyl sulfate polyacrylamide gel electrophoresis, a
technique to separate proteins based on size.
●● What is the active site of an enzyme?
Answer: The specific region where substrates bind, stabilizing the
transition state.
●● What does the Michaelis-Menten equation describe?
Answer: The rate of enzymatic reactions as a function of substrate
concentration.
●● What is competitive inhibition?
Answer: When inhibitors bind to the active site, increasing K_m while
V_max remains unchanged.
●● What is noncompetitive inhibition?
Answer: When inhibitors bind to an allosteric site, lowering V_max
without affecting K_m.
QUESTIONS WITH COMPLETE SOLUTION
PREMIUM REVIEW CONTENT
●● What is the Henderson-Hasselbalch equation used for?
Answer: It is used to calculate the pH of buffer solutions based on the
concentrations of the acid and its conjugate base.
●● What is the physiological pH maintained by the bicarbonate system
in blood?
Answer: Around 7.4.
●● How are amino acids classified?
Answer: Based on their side chain properties: nonpolar, aromatic, polar
uncharged, acidic, and basic.
●● What are zwitterions?
Answer: Molecules that possess both positive and negative charges at
physiological pH.
●● What is the isoelectric point (pI)?
Answer: The pH at which an amino acid has no net charge, calculated as
pI ≈ (pK₁ + pK₂)/2.
,●● What are fibrous proteins?
Answer: Proteins that provide structural support, with elongated
structures and repetitive secondary motifs, such as collagen and keratin.
●● What are globular proteins?
Answer: Compact and soluble proteins that perform diverse functions,
such as enzymes and hemoglobin.
●● What is the primary structure of a protein?
Answer: The linear sequence of amino acids that determines the
protein's unique characteristics.
●● What defines the secondary structure of a protein?
Answer: Regular patterns such as α-helices and β-sheets formed by
hydrogen bonding between backbone atoms.
●● What is the tertiary structure of a protein?
Answer: The three-dimensional shape formed by the folding of the
polypeptide chain, stabilized by various interactions.
●● What is the quaternary structure of a protein?
Answer: The assembly of multiple polypeptide subunits into a functional
protein complex.
, ●● What is chromatography used for in protein purification?
Answer: It separates proteins based on size, charge, or binding affinity.
●● What does SDS-PAGE stand for?
Answer: Sodium dodecyl sulfate polyacrylamide gel electrophoresis, a
technique to separate proteins based on size.
●● What is the active site of an enzyme?
Answer: The specific region where substrates bind, stabilizing the
transition state.
●● What does the Michaelis-Menten equation describe?
Answer: The rate of enzymatic reactions as a function of substrate
concentration.
●● What is competitive inhibition?
Answer: When inhibitors bind to the active site, increasing K_m while
V_max remains unchanged.
●● What is noncompetitive inhibition?
Answer: When inhibitors bind to an allosteric site, lowering V_max
without affecting K_m.
